• Title/Summary/Keyword: envelopes

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A Study on the Estimation of Fatigue Life for Asphalt Pavement (아스팔트 포장(鋪裝)의 피로수명예측(疲勞壽命豫測)에 관한 연구(研究))

  • Seo, Chae Yeon
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.3 no.1
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    • pp.43-51
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    • 1983
  • The fatigue failure envelopes for the prediction of the fatigue life of asphalt pavements were obtained from the results of laboratory fatigue test for asphalt mixture. The envelopes did not depend on the experimental temperature and the number of loading, and varied with the types of asphalts. In the case of dense graded asphalt concrete, the envelopes formed a single curve regardless of the penetration of the asphalt. On the other hand, the method for the fatigue life prediction was presented based on the envelopes obtained and the triple layered elastic theory developed by Burmister.

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Thermal Performance of TI-wall System (투과형단열재 부착 건물외피구조체의 열성능)

  • Yoon, Yong-Jin;Kim, Hea-Jeong;Kim, Byoung-Soo
    • KIEAE Journal
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    • v.4 no.3
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    • pp.121-128
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    • 2004
  • One of the most weak parts for energy loss through the whole building components are building envelopes. Lots of technbologies to increase the thermal performance of building envelopes have been introduced in recent years. Transparent insulation is a new technology for building insulation and has function both solar transmittance and thermal insulation. This study has been carried out to develope the transparent insulation panels and TI-wall system and to analyze the thermal performance of TI-wall system by experiments using test-cell and dynamic energy simulation program ESP-r 9.0. This system is regarded as a efficient building envelope system suitable for to reduce the heating and cooling load of the buildings in our country.

OPTICAL PROPERTIES OF AMORPHOUS ALUMINA DUST IN THE ENVELOPES AROUND O-RICH AGB STARS

  • SUH, KYUNG-WON
    • Journal of The Korean Astronomical Society
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    • v.49 no.4
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    • pp.127-136
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    • 2016
  • We investigate optical properties of amorphous alumina (Al2O3) dust grains in the envelopes around O-rich asymptotic giant branch (AGB) stars using laboratory measured optical data. We derive the optical constants of amorphous alumina over a wide wavelength range that satisfy the Kramers-Kronig relation and reproduce the laboratory data. Using the amorphous alumina and silicate dust, we compare the radiative transfer model results with the observed spectral energy distributions. Comparing the theoretical models with observations on various IR two-color diagrams for a large sample of O-rich AGB stars, we find that the amorphous alumina dust (about 10-40%) mixed with amorphous silicate better models the observed points for the O-rich AGB stars with thin dust envelopes.

DUST GRAINS IN AGB STARS AS SOURCES OF INTERSTELLAR DUST

  • SUH KYUNG- WON
    • Journal of The Korean Astronomical Society
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    • v.37 no.4
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    • pp.289-294
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    • 2004
  • The main sources of interstellar dust are believed to be dust envelopes around AGB stars. The outflowing envelopes around the long period pulsating variables are very suitable place for massive dust formation. Oxygen-rich silicate dust grains or carbon-rich dust grains form in the envelopes around AGB stars depending on the chemical composition of the stellar surface. The dust grains expelled from AGB stars get mixed up and go through some physical and chemical changes in interstellar medium. There are similarities and differences between interstellar dust and dust grains in AGB stars. The mass cycle in the Galaxy may be best manifested by the fact that the dust grains at various regions have many similarities and understandable differences.

Binary Nature Revealed in Circumstellar Spiral-Shell Patterns

  • Kim, Hyosun;Hsieh, I-Ta;Liu, Sheng-Yuan;Taam, Ronald E.
    • The Bulletin of The Korean Astronomical Society
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    • v.39 no.1
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    • pp.56.1-56.1
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    • 2014
  • With the advent of high-resolution high-sensitivity observations, spiral patterns have been revealed around several asymptotic giant branch (AGB) stars. Such patterns can provide possible evidence for the existence of central binary stars embedded in outflowing circumstellar envelopes. It is, however, not generally recognized that the binary induced pattern, vertically extended from the orbital plane, exhibits a ring-like pattern with an inclined viewing angle. I will first review the binary-induced spiral-shell patterns on the AGB circumstellar envelopes with the effect of inclination angle with respect to the orbital plane, of which large inclination cases reveal incomplete ring-like patterns. I will describe a method of extracting such spiral-shell from the gas kinematics of an incomplete ring-like pattern to place constraints on the characteristics of the (unknown) central binary stars. This first success may open the possibility of connecting the ring-like patterns commonly found in the AGB circumstellar envelopes and in the outer parts of (pre-)planetary nebulae and pointing to the conceivable presence of central binary systems, which may give a clue for the onset of asymmetrical planetary nebulae.

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ON TOR-TORSION THEORIES

  • GOLRIZ M.;BIJANZADEH M. H.
    • Communications of the Korean Mathematical Society
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    • v.20 no.2
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    • pp.209-219
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    • 2005
  • Tor-torsion theory was defined by Jan Trlifaj in 2000. In this paper we introduce the notion of Co envelopes, CoCovers and Tor-generators as dual of envelopes, covers and generators in cotorsion(Ext-torsion) theory and deduce that each R-module has a projective and a cotorsion coprecover.

A Study on the Energy Improvement Plan of using Passive Design with Exterior Envelopes and Renewable Energy for Bio Safety Labotratory (외피의 Passive Design 요소와 신재생에너지를 적용한 생물안전 밀폐시설의 에너지 시스템 개선방안 연구)

  • Hwang, Ji Hyun;Bum, Do;Hong, Jin Kwan
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.26 no.10
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    • pp.491-496
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    • 2014
  • In general, the entire air supply of a bio-safety laboratory (BSL) should be exhausted on the outside to ensure bio-safety, and the air conditioning system should always be operated to maintain a difference in the room pressure. As a result, the annual energy consumption of such a building is approximately five or ten times higher than that of an office building of the same magnitude. Thus, this study applies an actual operating system that targets BSL. The energy consumption is analyzed using the Energy Plus V8.0 program (an energy analysis program), and five kinds of cases that depend on the energy consumption of the basic BSL system are also analyzed. As a result, the energy consumption in Case 1 (basic system) is of 324.95 GJ. When the basic system of Case 1 is compared to that in Case 2 (basic system+passive design with exterior envelopes), an annual energy savings of is 6.9% is achieved. For Case 3 (basic system+Photovoltaic, PV) 12.7% is achieved, and for Case 4 (Solar Geothermal Hybrid System of renewable energy, SGHS) 49.5% is achieved. If a passive design with exterior envelopes and renewable energy system (PV+SGHS) is combined, as in Case 5, the energy consumption would be 118.15 GJ. Therefore, when this last system is compared to a basic system, the passive design with exterior envelopes and renewable energy system (PV+SGHS) can reduce energy consumption by 63.6%.

Defective Interfering HIV-1 Pseudotypes Carrying Chimeric CD4 Protein

  • Park, Seung-Won;Ye, Zhiping;Schubert, Manfred;Paik, Soon-Young
    • BMB Reports
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    • v.34 no.6
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    • pp.566-572
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    • 2001
  • Chimeric CD4 proteins were assembled. They contained the entire CD4 ectodomain that is linked to different membrane anchors. Membrane anchors consisted of either glucosyl phosphatidyl inositol (gpi), the transmembrane and cytoplasmic regions of HIV-1 Env protein, or the vesicular stomatitis virus G glycoprotein, respectively. The HIV-1 co-receptor CXCR4 and CD4 were independently inserted into viral envelopes. We compared the insertion of six different CD4/CXCR4 constructs into HIV-1 envelopes, as well as their functionality in targeting and specific infection of cells that constitutively express the HIV-1 Env protein. All of the six different HIV-1 (CD4/CXCR4) pseudotypes were able to transduce Env (+) cells at similar efficiency. In addition, stable transduction of the Env (+) recipient cells demonstrated that all chimeric proteins were functional as receptors for Env when inserted into HIV-1 envelopes. In fact, these results demonstrate for the first time a stable transduction by a targeted HIV-1 pseudotype virus.

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Comparative Ultrastructures of the Fertilized Egg Envelopes in Golden severum, Convic cichlid and Discus, Cichlidae, Teleost (경골어류 시클리드과 Golden severum, Convic cichlid 및 Discus의 수정란 난막 미세구조 비교)

  • Deung, Young-Kun;Reu, Dong-Suck;Kim, Dong-Heui
    • Applied Microscopy
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    • v.27 no.4
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    • pp.417-432
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    • 1997
  • The structures of the fertilized egg envelope in three species of cichlidae, golden severum (Cichlasoma severum var.), convic cichlid (Cichlasoma nigrofasciatum) and discus (Symphysodon aequifasciatus) were investigated by routine light and electron microscopies. The fertilized eggs of all three species were of the non-transparent, ellipsoidal, adhesive and non-floted type. The egg envelopes have a single micropyle, which is thought to the pathway of sperm in the area of the animal pole. In golden severum, an outer surface of egg envelope was covered by a reticular layer, that of convic cichlid was covered by an amorphous reticular layer and that of discus was covered by a branched reticular layer. The fertilized egg envelopes consisted of two distinct layers, an adhesive outer layer and an inner layer, consisted of lamellae alternating with interlamellae of lower electron density, in all three species; an inner layer of golden severum was $15\sim17$ layers, that of convic cichlid was $14\sim16$ layers, and that of discus was $18\sim19$ layers.

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A Knowledge-Based System for Address Block Location on Korean Envelope Images (우리나라 우편 봉투 영상에서의 주소 영역 추추을 위한 지식 기반 시스템)

  • 김기철;이성환
    • Journal of the Korean Institute of Telematics and Electronics B
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    • v.31B no.8
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    • pp.137-147
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    • 1994
  • In this paper,we propose a knowledge-based system for locating Destination Address Block(DAB) by analyzing the structure of Korean envelope images. In the proposed system the preprocessing steps such as adaptive binarization connected component extraction and deskewing are carried out first for the effective structure analysis of the envelope image. Then DAB containing address name and zipcode parts of the input envelope image is extracted by an iterative procedure based on the knowledge acquired from the statistical feature analysis of the various envelope images. Most of the system for slocating address blocks on envelopes have extracted DAB by segmenting an envelope image into several candidate blocks followed by selecting one among the candidate blocks. Because it is very difficult to segment a Korean envelope image into several blocks due to the specific writing habits that the addresses on the envelope are written in close proximity to each other the proposed iterative procedure determines DAB by splitting or merging the connected components and verifies the determined DAB without segmentation and selection. Experiments with a great number of the live envelopes provided from Seoul Mail Center in Koorea were carried out. The results reveal that the proposed system is very effective for address block location on Korean envelopes.

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